6 ideas
21548 | The null class is the class with all the non-existents as its members [MacColl, by Lackey] |
Full Idea: In 1905 the Scottish logician Hugh MacColl published a paper in which he argued that the null class in logic should be taken as the class with all the non-existents as its members. | |
From: report of Hugh MacColl (Symbolic Reasoning [1905]) by Douglas Lackey - Intros to Russell's 'Essays in Analysis' p.95 | |
A reaction: For the null object (zero) Frege just chose one sample concept with an empty extension. MacColl's set seems to have a lot of members, given that it is 'null'. How many, I wonder? Russell responded to this paper. |
10121 | Contradiction is not a sign of falsity, nor lack of contradiction a sign of truth [Pascal] |
Full Idea: Contradiction is not a sign of falsity, nor the lack of contradiction a sign of truth. | |
From: Blaise Pascal (works [1660]), quoted by A.George / D.J.Velleman - Philosophies of Mathematics Ch.6 | |
A reaction: [Quoted in Auden and Kronenberger's Book of Aphorisms] Presumably we would now say that contradiction is a purely formal, syntactic notion, and not a semantic one. If you hit a contradiction, something has certainly gone wrong. |
13554 | True greatness is never allowing events to disturb you [Seneca] |
Full Idea: There is no more reliable proof of greatness than to be in a state where nothing can happen to make you disturbed. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §06) | |
A reaction: He specifically opposes Aristotle's view that there are times when anger is appropriate, and failure to be very angry indeed is a failure of character. |
13556 | Every night I critically review how I have behaved during the day [Seneca] |
Full Idea: When the lamp has been removed from my sight, and my wife, no stranger now to my habit, has fallen silent, I examine the whole of my day and retrace my actions and words; I hide nothing from myself. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §36) |
13552 | Anger is an extreme vice, threatening sanity, and gripping whole states [Seneca] |
Full Idea: Other vices drive the mind on, anger hurls it headlong; ..other vices revolt from good sense, this one from sanity; ...other vices seize individuals, this is the one passion that sometimes takes hold of an entire state. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §01) | |
A reaction: He particularly dislikes anger because it is the vice that leads to violence. |
13553 | Anger is a vice which afflicts good men as well as bad [Seneca] |
Full Idea: Other vile passions affect only the worst sort of men, but anger creeps up even on enlightened me who are otherwise sane. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §04) | |
A reaction: A very interesting observation for anyone who is trying to analyse the key issues in virtue theory. |